Mechanism for ejecting plastic materials

ABSTRACT

An improved gun-handle type water pressure actuated mechanism for ejecting plastic materials from ordinary nozzle-ended cylindrical cartridges is described. A trigger-like lever when squeezed in the inward direction opens a first valve, permitting water under pressure supplied through an ordinary garden hose to fill and expand an expansible bladder constrained in the gun body so as to exert a force against a plunger adapted to engage and push inwardly upon the piston of a cartridge supported by the gun body, and thereby express the contained material through the cartridge nozzle. When the trigger lever is moved outwardly of the handle, a second valve is actuated to enable water under pressure within the bladder to escape through a flexible drain hose, thereby immediately releasing any pressure being exerted on the cartridge piston to stop the flow of material.

'ite States Patent n91 Stamets et al.

[451 Jan. 23, 1973 [S41 MECHANISM FOR EJECTING PLASTIC MATERIALS [7 6 'lnv entors: Melvin W. Stamets, l Dellwood Court, Ramsey, NJ. 07446; Charles E. Clauss, 1048 West Emaus Avenue, Allentown, Pa. 18103 [22] Filed: Nov. 12, 1971 [21] Appl.No.: 198,291

[52] US. Cl. ..222/326, 222/386.5, 222/333 [51] Int. Cl ..G0li 13/00 [58] Field of Search...222/333, 386, 386.5, 389, 326,

[56] References Cited UNITED STATES PATENTS 3,254,806 6/1966 Madsen ..222/333 X 2,859,808 11/1958 Y0ungquist et al. ...222/386.5 2,660,343 11/1953 Charpiat ..222/397 Primary ExaminerRobert B. Reeves Assistant Examiner-Joseph J. Rolla Attorney-James J. Cannon [57 ABSTRACT An improved gun-handle type water pressure actuated mechanism for ejecting plastic materials from ordinary nozzle-ended cylindrical cartridges is described. A trigger-like lever when squeezed in the inward direction opens a first valve, permitting water under pressure supplied through an ordinary garden hose to fill and expand an expansible bladder constrained in the gun body so as to exert a force against a plunger adapted to engage and push inwardly upon the piston of a cartridge supported by the gun body, and thereby express the contained material through the cartridge nozzle. When the trigger lever is moved outwardly of the handle, a second valve is actuated to enable water under pressure within the bladder to escape through a flexible drain hose, thereby immediately releasing any pressure being exerted on the cartridge piston to stop the flow of material.

MECHANISM FOR EJECTING PLASTIC MATERIALS This invention relates to improvements in the construction, operation and utility of fluid pressure operated mechanisms for the ejection of plastic materials. A common example of such mechanisms is the ordinary caulking gun.

One object of this invention is to provide an improved control over the discharge of caulking or other plastic material which is immediately responsive to the pressure exerted on the trigger thereof.

Another object of this invention is to provide an improved fluid pressure means for the operation of a mechanism for ejecting plastic materials capable of using readily available disposable cartridges of caulking or other plastic materials.

A further object of this invention is to provide a fluid pressure system for the operation of a mechanism for the ejection of plastic materials which can operate safely and simply with readily available sources of fluid pressure requiring no specialized equipment or operator training.

A further object of this invention is to provide an improved fluid pressure system for a mechanism for the ejection of plastic materials of relatively simple design and inexpensive construction.

The utilization of portable, hand-operated caulking guns and disposable cartridges of caulking or other plastic materials in the construction, maintenance and repair of buildings is very common today. Among the various mechanisms for the ejection of plastic materials (including caulking guns) presently available, the more common types operate by the exertion of manual pressure on a trigger type lever adapted to move a plunger rod forward into the cartridge magazine, thereby forcing plastic materials through a nozzle at the other end of the cartridge. The movement of the plunger rod is controlled by rachet teeth on the plunger rod which engage a gear'operated spring pawl movable forwardly with rearward rocking of the trigger. With this type of system it is impossible to control accurately theamount of caulking material forced out of the nozzle. The amount of material is a function of the distance between-the ratchet teeth and the number of teeth engaged in any single movement of the trigger. This lack of precise control frequently results in a flowof plastic material which is either too slow or too rapid for the application involved and very often in the excessive discharge of plastic material. The excessive application of such plastic materials andthe waste resulting from the inability to stop the discharge are caused by the necessity of moving the plunger rod forward a predetermined distance regardless of the requirements of the application. Some of these deficiencies may be overcome by operator efficiency and experience.

There are also available some mechanisms for the ejection of plastic materials which are operated by fluid or air pressure which can overcome most of the deficiencies of the manually operated mechanisms. Presently available fluid pressure operated systems are of complex construction and consequently are too expensive for the average user of a caulking gun. They also require a source of pressure such as an air compressor or similar device. Such sources of pressure are too expensive for the average user of a caulking gun. They also require skill and training for safe use and reduce the portability of the mechanism.

The present invention overcomes the deficiencies of both types of prior mechanisms for the ejection of plastic materials. By providing a fluid pressure system capable of precise control it overcomes the problem of precision in the application of caulking or other type of plastic material, eliminates waste since there is no predetermined minimal forward movement of the plunger, and is fully responsive to the needs of the operator. It also overcomes the deficiencies of the prior pressure operated mechanisms in several ways. It operates primarily by water pressure supplied by an ordinary garden hose connected thereto. This source of pressure is readily available and usually requires no further expenditure beyond the purchase of a gun and a section of hose, both far less expensive than an air compressor. Further, this simplified pressure system is readily portable, and is simpler and safer to operate and maintain than any air pressure system or fluid system requiring a compressor. Furthermore, the design of the fluid pressure mechanism within the handle has been simplified, resulting in a relatively low manufacturing cost and lighter weight.

The present invention utilizes the common caulking cartridge in a modified form of the common caulking gun. it includes a tubular barrel to hold the cartridge, which tubular barrel is attached to the gun body by a lock piece and held in place by lock pins. The gun body is also as tubular barrel with a conventional handle. Within the tubular portion of the gun body there is a cylindrical plunger, a flexible, expandible bladder and means of releasing a fluid under pressure into said bladder. As the bladder fills it exerts pressure upon the plunger, pushing a cartridge piston into the cartridge and forcing plastic material out of the nozzle of the cartridge. The control of pressure in the bladder is by means of a trigger-type lever in the handle of the gun body which activates spring-controlled valve plungers and can be activated gradually by pressure of the operators finger. When this operator pressure is released, the pressure in the bladder is simultaneously released and the flow of plastic material stops. The source of fluid pressure in the handle is ordinary water pressure from a standard household-type water faucet connected to the handle of the ejection mechanism by a piece of ordinary garden hose.

Although the preceding description is directed to the utilization of the invention to a common caulking gun, it is to be emphasized that the invention may be utilized in many applications calling for the controlled ejection of plastic materials.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein the numerals refer to like parts throughout, and in which? FIG. 1 is a longitudinal sectional view of the present fluid pressure operated mechanism; and

FIG. 2 is a transverse sectional view taken along a plane passing through sectional line 2-2 of FIG. 1.

Referring specifically to the drawings, reference numeral 10 designates, generally, a preferred form of fluid pressure operated caulking gun embodying the invention, the same being comprised of a cartridge cylinder 11, a gun body portion 12 and a gun handle portion 13.

The cartridge cylinder 11 is preferably in the form of a metal tube of such internal diameter as to receive, slidably fitted therein, an ordinary cylindrical cartridge C of a caulking compound or other plastic material to be dispensed through cartridge nozzle N. The front or outer end of the cartridge cylinder 11 is formed with an inturned peripheral lip portion 14 serving as a stop for the front end of a cartridge C inserted for use in the device. The rear end of the cartridge cylinder 11 has affixed thereto, in surrounding and outwardly projecting relation, a tubular collar 15 adapted to interfittingly receive a forwardly extending cylindrical end portion 16 of the gun body portion 12. The cartridge cylinder 11 is removably securable with respect to the outer end portion 16 of the gun body portion 12 by means of a pair of diametrically opposed headed retainer pins 17 extending outwardly of said gun body portion and adapted to be received in angular slots 18 provided in diametrically opposed relation in the tubular collar 15 (only one slot illustrated in FIG. 1).

The gun body portion 12 comprises a cylindrical recess 19 slidably received within which is a tubular plunger member 20 integrally formed with a front end wall 21 adapted to be received within and against the disk-like piston member P comprising a cartridge C. Freely disposed within the interior of cylindrical recess 19 of the tubular plunger 20 is an expansible bladder member 22, which may be of either natural or synthetic rubber, the rear open end of which is peripherally secured to the back end of the gun body portion 12 by means of a inner circular clamp plate 23 retained in place in interclamping relation by a circular outer end clamp plate 24. A pair of threaded stud members 25 extending outwardly of the inner circular clamp plate 23 and through openings in the outer end clamp plate 24 receive nuts 26 for retaining the open end of the bladder member 22 in sealed relation with respect of the inside of the inner clamp plate 23.

Means is provided for bleeding air pressure from within the bladder member 22 during the filling of the balloon with water as is herein below more particularly described. To this end, a headed valve member 27 having a rod-like valve stem 28 extends through an opening 29 in the inner circular clamp plate 23 and an opening 30 of increased diameter in the outer clamp plate 24. The outer end of the valve stem 28 carries a circular abutment button 31. A helical compression spring 32 circumjacent the valve stem 28 and constrained between an outside portion of the inner clamp plate 23 and the underside of the abutment button 31 normally urges the underside of the head of the valve member 27 and O-ring 33 against a peripheral valve seat provided at the inner end of the opening 29. It is to be noted that the diameter of the valve stem 28 is somewhat less than the diameter of the openings 29 and 30 through which it extends, so as to permit the free passage of pressurized air within the bladder member 22 upon pressing inwardly upon the valve button 30 during use of the device, as is hereinbelow described.

The gun body portion 12 is integrally formed with a downwardly projecting handle support portion 34. The handle support portion 34 is provided with vertically aligned upper and lower horizontally extending bores 35, 36, respectively, opening to the rear. The inner ends of the bores 35, 36 extend into reduced-diameter through openings 37, 38, respectively of decreased diameter, slidably received within which are respective upper and lower valve pins 39, 40. Fixed to the pin near the inner, rounded ends of the valve pins 39, 40 are thrust washers 41, 42, respectively. Compression springs 43, 44 circumjacent respective valve pins 39, 40 and constrained between the insides of said thrust washers and the inner ends of their respective bores 35, 36, normally urge said valve pins in their rearward most positions for the purposes hereinbelow more particularly described.

Means is provided for individually controlling the actuating of the valve pins 39, 40. To this end, the front of the handle support portion 34 is provided with a vertical slot 45, open at the lower end, within which is received an upper end portion of an elongated valve lever 46, whereat it is pivotally journalled by a transverse pivot pin 47. The pivot pin 47 is arranged in vertical alignment between outwardly projecting portions of the valve pins 39, 40, which valve pins extend horizontally through upper and lower openings 48, 49 of substantially increased diameter provided in the valve lever 46. The outwardly projecting ends of the valve pins 39, 40 are fitted with cross pins 50, 51 respectively, adapted to abut outside surface portions of the valve lever 46 upon operation of the device, as is hereinbelow described. The vertically extending back surface of the handle support portion 34 is substantially flat and has clamped thereagainst, in face-to-face relation, a vertical upper surface portion 52 of the gun handle portion 13. The gun handle 13 is secured in place as by machines screws (see FIG. 2). interposed between the clamped surfaces of the handle support portion 34 and the gun handle portion 13 is a resilient valve gasket and diaphragm member 13a, which may be of natural or synthetic rubber, for example.

The gun handle portion 13 is provided with upper and lower, horizontally extending bores 54, 55 in coaxial alignment with upper and lower valve pins 39, 40, respectively. The outer end of the upper bore 54 communicates with a threaded-in-place fitting 56 for connection with a water supply hose 57 (partially illustrated). The lower bore 55 communicates with a threaded-in-place fitting 58 connected to one end of a transfer tube 59, which may be of copper tubing. The other end of the transfer tube 59 connects with a fitting 60 threaded in the inner circular clamp plate 23 for communication with the interior of the bladder member 22.

The gun handle portion 13 is also provided with a third horizontally extending bore 61, intermediate the bores 54, 55 and laterally offset with respect thereto. The outer end of the third bore 61 communicates with a threaded-in-place fitting 62 adapted to connect with a flexible water drain conduit or hose 63 (partially illustrated in FIG. 2).

The flat back surface of the handle support portion 34 is provided with a first undercut or recess 64 communicating with and extending somewhat downwardly of the outer end of the upper bore 35, and a second undercut 65 communicating with and extending angularly upwardly to. terminate in register with the inner end of the intermediate bore 61 in the gun handle portion 13. The gun handle portion 13 is also provided with a central bore 66 communicating at its inner end with bore 55 and opening into the clamping surface of said gun handle at a position in register with the undercut 64.

In use of the device water under pressure is supplied through flexible conduit or hose 5''! connected to an or dinary household water supply faucet or hose bib, for example. Upon squeezing the trigger-like valve lever 46 towards the gun handle portion 13, the upper end of said lever will abut the cross pin 50 to withdraw the valve pin 39 against the resilient reactive force of compression spring 43, and thereby permitting the diaphragm 13a to be displaced under water pressure into undercut 64, whereupon water will be able to flow through bores 54, 66 and 55, and through transfer conduit 59, into the interior of bladder member 22. While water under pressure is thus being supplied to the bladder 22, the abutment button 31 will be depressed, allowing any air in the bladder to escape while being replaced by the water. Thereafter, the abutment button 31 will be released to prevent the escape of water through opening 29. As long as the valve lever 46 is thus actuated, water under pressure being supplied to the bladder member 22 will continue to expand said bladder against the front end wall 21 of the tubular plunger 20, causing said plunger to force the tube piston P forwardly and thereby express the contained caulking or other semi-fluid plastic material through the nozzle N. It is to be noted that by positionally controlling the trigger-like valve member 46, water under pressure can be supplied to the bladder member 22 at an adjustable rate in accordance with the designed flow rate of the plastic material through the nozzle N.

In order to stop the flow of caulking or other plastic material from the cartridge C, it is only necessary to release valve lever 46 so that valve pin 39 returns to its inwardmost position, whereat it will seal the diaphragm 13a against the inner end of bore 54 to stop the flow of pressurized water into the expansible bladder member 22. If the valve lever 46 is now pushed away from the gun handle portion 13 instead of being squeezed toward it as described above, abutment of said lever with the cross pin 51 of the valve pin 40 will cause said valve pin to be withdrawn, against the urging of compression spring 44, to permit the diaphragm 13a, normally sealed against the inner end of the bore 55 to move into the second undercut 65. Pressurized water contained in the bladder member 22, even if only under slight pressure, will thus be allowed to escape or oven flow through flexible water drain conduit 64, and thereby immediately stop the flow of caulking or other plastic material being dispensed.

Although the present invention has been described in terms of its utilization as a caulking gun, it will be noted that the present invention may be effectively employed in many applications calling for the ejection of plastic materials from a tube or cartridge. 'Thus the present invention has wide application in the construction arts and in other industrial applications.

The foregoing is considered as illustrative only of the principles of the invention. Further since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

1 claim: 1

l. A fluid pressure operated mechanism for ejecting plastic materials from removable cartridges from such materials comprising, a cartridge barrel adapted to contain a cartridge of plastic material, a gun body member having a cylindrical recess, clamping means for attaching said cartridge barrel to said gun body member in end-toend coaxial relation with respect to said cylindrical recess, a gun handle member on said gun body member, a tubular plunger closed at one end within said cylindrical recess for forcing material out of the cartridge, an expansible, open-ended bladder within said plunger, a clamp plate attaching the open end of the said bladder to said gun body member and providing a fluid-tight connection, means for releasing air pressure within said bladder, means for supplying a fluid under pressure within said bladder, and means for eliminating the fluid from within said bladder.

2. A fluid pressure operated mechanism for ejecting plastic materials as defined in claim 1, wherein said means for releasing air pressure within the bladder comprises a headed valve stem member the head of which is within the bladder, the other end of said valve stem projecting outward through an increased diameter opening in said clamp plate, and O-ring around said valvestem member within said bladder and underneath the head of said valve stem member to provide a fluidtight seal at the inner end of said clamp plate opening, a button on the exterior end of said valve stem member, and a compression spring around said 'valve stem member between said clamp plate and said button.

3. A fluid pressure operated mechanism for ejecting plastic materials as defined in claim 1, wherein said means for supplying a fluid under pressure to the bladder comprises a first normally closed valve means in said gun body member, means for connecting a flexible supply hose to the inlet side of said normally closed valve means, means including a trigger-like lever member pivotally connected with said gun. body member for opening said first valve means, and conduit means communicating between the outlet side of said normally closed valve means and the inside of said bladder.

4. A fluid pressure operated mechanism for ejecting plastic materials as defined in claim 3, wherein said first normally closed valve means comprises a first bore in said gun body member and a flexible diaphragm, ex-

. tending laterally across one end of said first bore, said means for opening said first valve means comprising a valve pin and means normally urging said valve pin against an outside portion of said diaphragm for normally retaining said diaphragm in sealing relation with respect to said one end of said bore.

5. A fluid pressure operated mechanism for ejecting plastic materials as defined in claim 4, wherein said means for eliminating the fluid from within said bladder comprises a second normally closed valve means in said gun body, means for connecting a flexible discharge hose to one side of said second normally closed valve means, means including said trigger like lever member for selectively opening said first valve means and said second valve means, and conduit means communicating between the other side of said normally closed second valve means and the inside of said bladder.

6. A fluid pressure operated mechanism for ejecting plastic materials as defined in claim 5, wherein said second normally closed valve means comprises a .second bore in said gun body member, said flexible said second valve means comprises a first opening in said trigger-like lever member through which said first valve pin extends, and a second opening said in trigger member through which said second valve pin extends, said lever member being pivotally joumalled between said first and second lever member openings, and abutment means extending laterally outwardly of the outer ends of each of said first and second valve pins for selective abutment by said lever member. 

1. A fluid pressure operated mechanism for ejecting plastic materials from removable cartridges from such materials comprising, a cartridge barrel adapted to contain a cartridge of plastic material, a gun body member having a cylindrical recess, clamping means for attaching said cartridge barrel to said gun body member in end-to-end coaxial relation with respect to said cylindrical recess, a gun handle member on said gun body member, a tubular plunger closed at one end within said cylindrical recess for forcing material out of the cartridge, an expansible, open-ended bladder within said plunger, a clamp plate attaching the open end of the said bladder to said gun body member and providing a fluid-tight connection, means for releasing air pressure within said bladder, means for supplying a fluid under pressure within said bladder, and means for eliminating the fluid from within said bladder.
 2. A fluid pressure operated mechanism for ejecting plastic materials as defined in claim 1, wherein said means for releasing air pressure within the bladder comprises a headed valve stem member the head of which is within the bladder, the other end of said valve stem projecting outward through an increased diameter opening in said clamp plate, and O-ring around said valve stem member within said bladder and underneath the head of said valve stem member to provide a fluid-tight seal at the inner end of said clamp plate opening, a button on the extErior end of said valve stem member, and a compression spring around said valve stem member between said clamp plate and said button.
 3. A fluid pressure operated mechanism for ejecting plastic materials as defined in claim 1, wherein said means for supplying a fluid under pressure to the bladder comprises a first normally closed valve means in said gun body member, means for connecting a flexible supply hose to the inlet side of said normally closed valve means, means including a trigger-like lever member pivotally connected with said gun body member for opening said first valve means, and conduit means communicating between the outlet side of said normally closed valve means and the inside of said bladder.
 4. A fluid pressure operated mechanism for ejecting plastic materials as defined in claim 3, wherein said first normally closed valve means comprises a first bore in said gun body member and a flexible diaphragm, extending laterally across one end of said first bore, said means for opening said first valve means comprising a valve pin and means normally urging said valve pin against an outside portion of said diaphragm for normally retaining said diaphragm in sealing relation with respect to said one end of said bore.
 5. A fluid pressure operated mechanism for ejecting plastic materials as defined in claim 4, wherein said means for eliminating the fluid from within said bladder comprises a second normally closed valve means in said gun body, means for connecting a flexible discharge hose to one side of said second normally closed valve means, means including said trigger like lever member for selectively opening said first valve means and said second valve means, and conduit means communicating between the other side of said normally closed second valve means and the inside of said bladder.
 6. A fluid pressure operated mechanism for ejecting plastic materials as defined in claim 5, wherein said second normally closed valve means comprises a second bore in said gun body member, said flexible diaphragm extending laterally across one end of said second bore, said means for opening said second valve means comprising a second valve pin, and means normally urging said second valve pin against an outside portion of said diaphragm for normally retaining said diaphragm in sealing relation to said one end of said second bore.
 7. A fluid pressure operated mechanism for ejecting plastic materials as defined in claim 6, wherein said means for selectively opening said first valve means and said second valve means comprises a first opening in said trigger-like lever member through which said first valve pin extends, and a second opening said in trigger member through which said second valve pin extends, said lever member being pivotally journalled between said first and second lever member openings, and abutment means extending laterally outwardly of the outer ends of each of said first and second valve pins for selective abutment by said lever member. 